Rivian Automotive, Inc. (RIVN) shares tumbled 5.28% in trading, as investors reacted to the electric vehicle maker's first-quarter delivery report. Despite meeting expectations, the significant year-over-year decline in deliveries raised concerns about the company's growth trajectory in an increasingly competitive EV market.

Rivian announced that it delivered 8,640 vehicles in the first quarter of 2025, marking a 36% decrease compared to the same period last year. While this figure was in line with both company guidance and market expectations, the sharp drop hinted at potential demand or production challenges. The company also reaffirmed its full-year 2025 delivery guidance of 46,000 to 51,000 vehicles, but the lack of an upward revision likely contributed to the negative sentiment among investors.

The market's reaction to Rivian's report stands in stark contrast to its response to Tesla's disappointing Q1 deliveries. While Tesla's stock managed to recover and close higher on unrelated news, Rivian's shares remained under pressure throughout the trading session. This disparity highlights the challenges facing smaller EV manufacturers as they compete for market share against more established players in a rapidly evolving industry.